Electromagnetic vibratory unit



May 29, 192s. 1,671,727

J. M. S. KING ET AL ELECTROMAGNETI C VIBRATORY UNI T Filed Jan, 1.4, 1926 Patented May 29, 1928.

` UNITED STATES PATENT OFFICE.

JOSEPH M. S. KING AND ROSS S. LUND, OF SALT LAKE CITY, `UTAH, ASSIGNORS T0 UTAH RADIO PRODUCTS COMP-ANY,v OF SALT LAKE CITY, UTAH,l A CORPORATION 0F UTAH.

ELECTROMAGNETIC VIBIRATORY UNIT.

Application filed January 14., 1926. Serial No. 81,348.

This invention relates to an improved electromagnetic vibrating unit, and its principal objects are to provide adevice *which shall:

First. Be extremely simple. A

Second. Be arranged with the utmost regard for economical production.

Third. Employ the magnetic fiux in an eiiicient manner: that is, reduce the leakage losses to a minimum. l

Fourth. Be sturdy and durable in service.

The competitive conditions in the field which this instrument serves, have made it necessary to take recognition of. the utmost possible economies of manufacture and production. p'

Therefore, in attaining the objects previously outlined, we have, in our present invention, endeavored to take advantage of every avenue that seemed tooffer-any possibilities for lessening costs, while at the same time maintaining a high standard of quality and strument.

To this end we have simplified our in'- strument, first, where the economy of labor and material entering into each individual part is concerned, and second, where the assembling of the individual parts intothe finished combination is concerned.

Our` invention is not intended to be revolutionary in its general character, but merely, to achieve the desired end in the most direct and economical manner.

The features for which the protection of letters patent is desired, are collectively grouped in the claims which conclude. this specification. i Y

In the drawing, which represents one embodiment of our invention:

Fig. lis a plan, the usual casing and other incidentals being omitted;

Fig. 2, a front elevation; and

Fig. 3, a longitudinal, vertical center Section.

Fig. 4, a transverse vertical section taken -on the center line of the electromagnet.

performance in the finished infv pole pieces 15 and -25 pole piece to have,

ception of the clamping studs 12 and 12-1 near the ends of the legs 10-1 and 10-2, of the `U. It will be seen that the magnet may be made of a. generous size, the crosssection of the bar being preferably of substantial uniformity throughout, thus maintaining the width ,anddepth of the original bar and resultin in ends which are neither offset to'lie in itferent planes, nor diagonally disposed and vspaced apart in two planes, as in other devices of which we are aware, but on the contrary, are non-offset to offsetting the ends,

lie in the same planes. of the magnet adds materially to the expense of production, and instead of improving the magnetic conditions, actually impairs the most -efricientaction of the magnetic flux by establishing additional poles at the offset portions of the magnets, thus uselessly diverting. part of the linx.

The spool 14 of the electromagnet is of such slze that it may be clasped exactly with- 1n the opening between the legs of the U,

' these being dpreferably p arallel to each other as indicate in Figs. 1 and 2,.where the length of the spool is equalto the inside distance between the magnet legs, and the height of the spool is equal to the height of the magnet bar, the height being determined by' the perpendicular distance between two mutually parallel planes defining the principal faces\of the-permanent magnet. The two pole pieces, 15 and 25 may be exactly alike and have the rearwardly extending lugs 15-1 and l25-1, as well as the forwardly inclined side flanges 15--2 and 25-2. A cross-section taken through the within the compass of the side flanges, shows the section of each in general, a backvportion from which the above mentioned side fianges depend,- as indicated in Fig. 3. lInasmuch as the inner facesof the lugs l-land 15-2 lie in the same plane with the inner faces of the said back portions, and further, that the flanges are spaced apart from each other substantially the same distance as the the spool is securely heldv in place without .the necessityo any other fastening means.

In Fig. 2, it will be seen that the side flanges 15-2 and 25-2, of the pole pieces, extend toward each other from their junction with the lugs15-1 and 25--1l respectively, thus lying virtually in a band, in this element.

diaphragm of ordinary construction (not shown), or to any other desired vibratory The assemblage thus far described, may

Vbe mounted upon any suitable base such as the ring 18,

and be fastened by threading the clamping studs l2 and 12-1 therein, as clearly shown in Fig. 4, the stud 12 being arranged to clamp the magnet against the intervening lng 254-1, while the stud 12-1 clamps the magnet against the intervening washer 19.

In emphasizing the simplicity of construction of this instrument, it is to be noted V that, (a) fthe magnet and spool are both perfectly lain Without any special fastening inem ers whatsoever; (b) the pole pieces are extremely simple and may be produced as plain stampings; (c) in assembling, the pole pieces are held spaced apart from each other to a precise gauge, upon vthe mutually opposed faces of the'legs of the magnet, while the spool` holding the coil of "the electromagnet is most securely clasped in the three principal directions as specified following: longitudinally, by the legs of the magnet; sideways by litt-ing in closely be tween the flanges 15-2 of the pole pieces;

`and vertically, by itting in closely between the inner faces of the backso the pole pieces 15 and25.

The advantage of the diagonal band .construction ofv the polerpie'ce flanges, consists in the fact that the `lealra,g ge of the I magnetic flux acrossthe space between the legs 10e-1 and 10-2 ofthe permanent magnet. and respectively, the end faces 2.5-3 and 15-3 of the poles-pieces (Fig. 2), is reduced to a minimum. i A

If the end faces of the anges 15-2 and `25--2, were lto extend vertically from the edges of the armature, then the faces 15-3 and 25-.3 would be considerably nearer to Lerma? the legs of 'the permanent magnet, thereby increasing very materially the leakage losses in the magnet-1c flux.

`Wliile a specific embodiment of this invention is herein shown and described, all the detailed parts may, or may not, be in the preferred forms, and further, the preferred forms may be varied fromV time to ltime as the development of the invention and the arts to which it appertains, progress. Therefore, that which forms an essential part of this invention will be discernible from the claims in which its spirit is generalized.

Having fully described our invention, what We claim is: l

1. A U-shaped permanent magnet, a coil having a. spool held in position along its longitudinal dimension by the legs of said magnet, the height of said spool being substantially equal to the perpendicular dis-,-

tance between the two principal planes of,

the said magnet,pole pieces having surfaces lying substantially in the said planes, said 'pole pieces being thereby precisely spaced apart td define a gap between them, the said spoolA beingheld against vertical displacement by bearing against the said snraces of the pole pieces, the pole pieces further, having side flanges defined by parallel edges extending obliquely across the. flange area of the said spool, said side flanges being spaced apart from veach other to hold the s ool against lateral displacement.

2. permanent magnet having legs spaced apartv from each other, an electromagnet located between the said legs, and by contact therewith held against displace-V ment along its longitudinal dimension, pole pieces extending inwardly from the two opposing principal planes of the'said permanent magnet, said pole pieces having side flanges lying in bands having ort-hographic projections defined by parallel lines which extend obliqnely across the orthographic end projection of the said permanent magnet, said pole pieces being arranged, by contact only, to hold the electromagnet against lateral and vertical displacement.-

In testimony Whereo, we sign our names hereto.

Jessen M. s. nine. ness s. nenn.

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